LyX is an advanced open source document processor running on many Unix
platforms. It is called a "document processor", because unlike standard
word processors, LyX encourages an approach to writing based on the
structure of your documents, not their appearance. LyX lets you
concentrate on writing, leaving details of visual layout to the software.
LyX automates formatting according to predefined rule sets, yielding
consistency throughout even the most complex documents. LyX produces high
quality, professional output -- using LaTeX, an open source, industrial
strength typesetting engine, in the background.

With LyX, short notes or letters are a snap. LyX really shines, though,
when composing complex documents like technical documentation, doctoral
theses and conference proceedings.